Feb. 8 (UPI) -- In 1945, researchers detonated the first nuclear bomb at a test site in the New Mexico desert. More than 70 years later, fragments of radioactive glass collected at the Trinity test site helped scientists test the validity of popular moon-formation theories.
The light green glass is called trinitite, or atomsite. It is composed of sand -- mostly quartz grains and feldspar -- melted but the extreme temperatures of the plutonium blast.
Scientists measured the concentrations of volatile elements like zinc in the glass fragments, collected 30 feet and 800 feet from the blast site. Glass closest to ground zero featured less zinc, and the zinc that remained was richer in heavier isotopes.
"The results show that evaporation at high temperatures, similar to those at the beginning of planet formation, leads to the loss of volatile elements and to enrichment in heavy isotopes in the left over materials from the event," James Day, a geoscientist at the Scripps Institution of Oceanography at the University of California San Diego, said in a news release. "This has been conventional wisdom, but now we have experimental evidence to show it."
Many scientists believe the moon was formed from molten debris ejected when a Mars-sized planetary object collided with Earth. Such a violent collision would have vaporized volatile elements in glassy debris, just as the Trinity fire ball robbed trinitite of its zinc.
Sure enough, when scientists compared trinitite samples and lunar rocks, they found depleted volatile elements and little to no water in both. The findings -- detailed in the journal Science Advances -- support the "giant impact theory."
"We used what was a history-changing event to scientific benefit, obtaining new and important scientific information from an event over 70 years ago that changed human history forever," concluded Day.
